Guard door-key.



W. s. MYERS & T. ALEXANDER.'

GUARD DOOR KEY.

APPLICATION FILED JUNE 5, 1909.

958,667., Pateni ed May 17, 1910.

ANDREW a GRAHAM co. Paom-mnonnnmzns WASH N5 WILLIAM S. MYERS AND TRUMAN ALEXANDER, OF ASHLAND, KENTUCKY.

GUARD DOOR-KEY.

Specification of Letters Patent.

Application filed June 5, 1909.

Patented May 17, 1910.

Serial No. 500,366.

To all whom it may concern:

Be it known that we, WILLIAM S. MYERS and TRUMAN ALEXANDER, citizens of the United States, residing at Ashland, in the count-y of Boyd and State of Kentucky, have invented new and useful Improvements in Guard Door-Keys, of which the following is a specification.

The present invention is an improvement in guard door keys, and it has for its principal object the production of a device of the general type specified, designed for insertion in the key hole of a door subsequent to the locking operation, to prevent the look from being opened or picked by either a duplicate or a skeleton key.

Briefly described, the improved guard key comprises relatively rotatable guard and locking members, the latter member being provided with a pair of spaced feet arranged for engagement with the opposite faces of the inner escutcheon plate, while the first mentioned member is provided with anaxially-elongated foot adapted to extend completely through the openings in both lock plates and to plug the opening in the outer escutcheon plate. The connection between the two members above described is effected through the medium of a split clamping sleeve formed integral with the locking member and fitted upon the reduced stem of the guard member.

The preferred embodiment of the invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of the improved guard key. Fig. 2 is a side elevation, partly in section. Fig. 3 is a transverse section taken on the line 33 of Fig. 2. Figs. 4: and 5 are partly sectional edge views of a door lock illustrating the two positions of the guard key.

Reference being had to said drawings, and

to the numerals marked thereon, 5 designates, in a general manner, the casing of a lock of any suitable type seated in the ordinary manner in the recess 6 formed in the door 7; 8 the front plate of said lock; and 9 and 10 the inner and outer escutcheon plates.

The improved key which operates in conjunction with the above-mentioned parts comprises essentially, a guard member 11 and a locking member 12. The latter member includes a finger-piece 13, a foot 14: integrally connected therewith, a split clamping sleeve 15 formed integral with said foot, and a second foot 16 which is likewise integral with said sleeve and lies at the side and in the plane of the firstmentioned foot, the mutually adjacent faces of the two feet being spaced apart a distance slightly greater than the thickness of the inner escutcheon plate. The length of the second or smaller foot is about one-third that of the first or main foot.

The sleeve 15, above referred to, is fitted upon the reduced stem portion 17 of the guard member 11 whose shank 18 is formed with an axially-elongated foot 19, longitudinal movement of the sleeve in one direction being prevented by the adjacent end of the shank and in the other direction by a head 20 formed upon the free end of the stem. The sleeve normally exercises a gripping or binding action upon the stem.

Prior to the operation of the guard key, the bolt (not shown) of the lock is shot by means of the key proper, after which the key is removed. The locking member of the guard key is then turned by means of its finger-piece 13 until the feet 14 and 16 are in line with the elongated foot 10, whereupon said guard key is inserted through the keyhole 21, in the inner escutcheon plate. The inward movement of the key is continued until the main foot let strikes against said plate, the width of the foot in question being slightly greater than the length of the key-hole, as shown in Fig. 4:. In this position, the free end of the shank 18 projects into the key-hole 22 in the outer escutcheon plate, the elongated foot extends completely through both key-holes 23 and 24 in the sides of the lock casing 5, and the foot 16 lies between the inner side of said casing and the inner escutcheon plate. If, then, the locking member be rotated so as to move the foot 16 out of registration with the key-hole 21, as

shown in Fig. 5, removal of the key will be effectually prevented until said member is returned to its initial position, since a portion of the outer escutcheon plate will be disposed between the feet 1 1 and 16. Consequently, it will prove impossible to open the lock either by a duplicate or a skeleton key, inasmuch as the key-hole 22 is closed or plugged by the end of the shank 18 and the adjacent end of the elongated foot.

In connection with the above, it may be stated that the invention, as described, is particularly Well adapted for use in hotels,

boarding houses, and the like, the key proper of each room having attached thereto 1n any suitable manner a guard key which may be operated after the door has been locked by the main key and the latter then withdrawn.

What is claimed is:

1. In a key of the type specified, the combination of a guard member; and a locking member rotatably connected thereto and comprising a sleeve, a pair of spaced feet formed integral with the sleeve and occupying a common plane, and a finger piece formed integral; with one foot.

2. In a key of the type specified, thecombination of a guard member including a shank, a stem, and a foot formed upon said shank; and a locking member comprising a sleeve rotatably fitted upon said stem, and a pair of spaced feet connected to said sleeve and occupying a common plane.

In testimony whereof we have hereunto set our hands in presence of two subscribing witnesses.

WILLIAM S. MYERS. TRUMAN ALEXANDER. Witnesses:

J. G. HUGHES, I. AUSTIN KELLY. 

